The present invention describes improvements in a digital mirror stage lighting system. More specifically, the present invention describes techniques which are used to improve operation in the special environment produced by the digital mirror stage lighting system.
Stage lighting systems have increased in complexity in recent years. It is desirable to be able to change literally any aspect of the beam projected by a stage light from a remote location. Light and Sound Design, the assignee of the present application, have suggested in other patents and applications that many of these issues could be improved by a stage lighting system that uses an active, x, y addressable element with a digital micromirror device (xe2x80x9cDMDxe2x80x9d) available from Texas Instruments. These devices use an array of controllable mirrors to selectively reflect light in pixel units. These devices have also been called digital mirror, digital light processor (DLP), and other names. Light can be selectively reflected in units of picture elements or pixels. This allows total control of light shape and certain other characteristics. Other devices which are controllable to selectively change characteristics of pixels of light, such as a grating light valve (GLV), can also be used for this purpose.
These concepts are disclosed in several pending patent applications of Light and Sound Design, including Ser. No. 08/854,353, the disclosures of which are herewith incorporated by reference to the extent necessary for proper understanding.
The pixel based light processors, however, themselves produces certain issues, including control issues and cooling issues. The present disclosure describes these and other issues which were found to exist, and describes certain solutions found by the inventors to combat these issues.
A number of aspects are described according to the present invention, and the following summary explains at least some of these aspects.
A first aspect includes control of the digital mirror device (DMD) and other associated operations. The control is typically completely digital, and many of the operations are carried out entirely mathematically. Therefore, a distributed control with a first control element that carries out mathematical calculations and a second control element which is optimized for control is desirable.
According to an aspect of the embodiment, the second control element is affected out entirely by a programmable gate array, such as a field programmable gate array or similar configurable device. A particularly preferred embodiment reconfigures the device after bulb startup, to avoid noise danger during the bulb startup.
Another aspect is that the digital mirror has loses a certain amount of light. This has required brighter, and hence more power intensive, bulbs. One aspect of this invention is relates to how the operation occurs to keep the heat of the bulb and ignition of the bulb from affecting the other subsystems.
The great amount of heat has produced the need for advanced cooling techniques. However, the digital mirror has specialized temperature requirements. According to this aspect, a pulse-driven thermoelectric cooler is used and the pulse width to the cooler is changed to change the amount of cooling.
Other aspects of this invention describe the way in which the control element carries out the operation.